fulltext.study @t Gmail

Heterogeneous structure and in vitro degradation behavior of wet-chemically derived nanocrystalline silicon-containing hydroxyapatite particles

Paper ID Volume ID Publish Year Pages File Format Full-Text
941 69 2013 12 PDF Available
Title
Heterogeneous structure and in vitro degradation behavior of wet-chemically derived nanocrystalline silicon-containing hydroxyapatite particles
Abstract

Nanocrystalline hydroxyapatite (HAp) and silicon-containing hydroxyapatite (SiHAp) particles were synthesized by a wet-chemical procedure and their heterogeneous structures involving a disordered phase were analyzed in detail by X-ray diffractometry (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and solid-state magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. The effects of heterogeneous structure on in vitro biodegradability and the biologically active Ca(II)- and Si(IV)-releasing property of SiHAp particles were discussed. The 29Si NMR analysis revealed that the Si(IV) was incorporated in the HAp lattice in the form of Q0(SiO44-orHSiO43-) species, accompanied by the formation of condensed silicate units outside the HAp lattice structure, where the fraction and amount of Q0 species in the HAp lattice depends on the Si content. The 31P and 1H NMR results agreed well with the XRD, TEM and FTIR results. NMR quantitative analysis results were explained by using a core–shell model assuming a simplified hexagonal shape of HAp covered with a disordered layer, where Si(IV) in Q0 was incorporated in the HAp lattice and a disordered phase consisted of hydrated calcium phosphates involving polymeric silicate species and carbonate anions. With the increase in the Si content in the HAp lattice, the in vitro degradation rate of the SiHAps increased, while their crystallite size stayed nearly unchanged. The biologically active Ca(II)- and Si(IV)-releasing ability of the SiHAps was remarkably enhanced at the initial stage of reactions by an increase in the amount of Si(IV) incorporated in the HAp lattice but also by an increase of the amount of polymeric silicate species incorporated in the disordered phase.

Keywords
Silicate; Calcium phosphate; Hydroxyapatite; Degradation; Apatite formation
First Page Preview
Heterogeneous structure and in vitro degradation behavior of wet-chemically derived nanocrystalline silicon-containing hydroxyapatite particles
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Acta Biomaterialia - Volume 9, Issue 1, January 2013, Pages 4856–4867
Authors
, , , , , , , , , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us